The present disclosure is directed to electronic backplanes and more particularly to backplanes which employ bendable flexible substrates.
Backplanes carry electronic components including but not limited to transistors (e.g., thin film transistors (TFTs), etc.) which are addressed via gate lines and data lines.
Traditionally, backplanes have been fabricated with glass substrates, resulting in rigid backplanes, which limits the areas where they may be employed. Therefore there is the present interest in manufacturing backplanes with bendable flexible (e.g., plastic, polymers, etc.) substrates in order to increase the overall bendability or flexibility of the backplane itself, which expands the areas where they may be used.
An issue concerning bendable flexible backplanes is however, the electronics used to address the electronic devices of the backplane (e.g., TFTs, etc.). Such electronics include chip-on-flex (COF) packages and/or printed circuit boards (PCBs). These electronics have much less bendability flexibility than the bendable flexible substrate. Therefore, when using common backplane architecture the benefit of the bendable flexible substrate is diminished. Particularly, in such architecture the sets of addressing lines (e.g., data addressing lines and gate addressing lines) run substantially in horizontal and vertical manners crossing each other (though in different metal layers and isolated from each other) at substantially 90 degrees. This arrangement causes the associated addressing electronics (e.g. the chip on flex (COF) packages, PCBs, etc.) to be positioned on adjacent sides of the backplane which acts to restrict the overall flexibility bendability of the backplane.
The present disclosure is directed to the design and manufacture of backplanes which overcome the existing limitations in order to increase bendability and flexibility.